Tuesday, June 29, 2010

Two radar satellite images (black and white) taken by the RADARSAT-1 and RADARSAT-2 satellites on June 27, 2010, show oil slicks and sheen extending across 19,112 square miles (49,500 km2) in the Gulf. The radar images were acquired at 6:48 am (long image on right) and 6:52 pm (image on left) local time:

Large bands of clouds containing strong thunderstorms are moving into the northern Gulf and affecting the area of the leaking Macondo oil well, raising the anxiety level surrounding the cleanup and response operation, but Alex is forecast to move steadily northwest, making landfall around the Texas-Mexico border:

Sunday, June 27, 2010

MODIS satellite images on June 25 and June 26 show oil slicks and sheen affecting beaches from Gulfport, Mississippi to Destin, Florida.

Oil slick and sheen cover 24,453 square miles on the June 25 image. Slicks appear to impacting beaches from Gulfport, Mississippi to Pensacola, Florida. Freshly upwelling oil is apparent at the site of the leaking Macondo well, and is moving west in the immediate vicinity of the well:

MODIS/Terra satellite image taken June 25, 2010

On June 26, a MODIS/Aqua satellite image shows oil slick and sheen covering 23,049 square miles, threatening beaches from Gulfport and Biloxi to Destin, Florida. To the west, the slick extends to Port Fourchon, Louisiana. Emerging oil is continuing to move west from the well site:

Friday, June 25, 2010

Dr. Oscar Garcia-Pineda of Florida State University has been out in the Gulf this week on the research vessel Brooks McCall. He's collecting samples and observations of the BP oil slick, and will compare results with simultaneous acquisitions of aerial remote sensing overflights being conducted by NASA. We at SkyTruth are also collecting near-simultaneous satellite imagery to assist this effort. We hope to get a better understanding of how well aerial and satellite remote sensing are detecting oil at (or near) the surface.

Oscar sent us a stunning series of photographs taken on June 22 near "Ground Zero" in the Gulf, the site of the leaking Macondo well, showing the cluster of response vessels there, and the collection and burning of oil. You can see them all in SkyTruth's Deepwater Horizon Blowout gallery (look for the photos with "FSU Sampling Cruise" in the title). Here are a few:

Natural gas and oil being flared off the Q4000 semisubmersible drillship. This oil and gas is part of the flow being collected from the leaking Macondo well on the seafloor at the blowout preventer, and diverted up to vessels at the surface. Photo courtesy Dr. Oscar Garcia-Pineda.

Oil being "corraled" at the surface with fireproof boom, then ignited. Photo courtesy Dr. Oscar Garcia-Pineda.

We superimposed three CSK radar satellite images (black-and-white) on a cloudy MODIS satellite image (color) taken about 1:00 pm on June 22, 2010. The long strip of CSK radar on the left was acquired at 12:08 UTC (7:08 am local time) on June 23; the two smaller images on the right were taken at 4:44 pm and 7:32 pm local time on June 22:

Areas of strong gusty wind appear as large bright patches on these radar images, especially in the east and along the Florida panhandle. Strong isolated thunderstorms, mostly on the June 23 image to the west, create circular "footprints" on the ocean surface caused by strong radial winds. Small bright patches associated with these storms are not clouds, but are high-altitude layers of hail or large water droplets in these storm cells that reflect radar energy.

Weather data buoys in the vicinity (stations 42040 and 42012) recorded wind speeds of 6-8 meters/second (13-18 miles/hr) when these images were acquired, strong enough to break up areas of thin oil sheen and possibly render them undetectable. We infer that the dark areas enclosed within the orange line are thicker patches of oil slick.

If the LMRP should break down, gunk up, or otherwise fail, is there a backup LMRP ready and waiting to be immediately deployed?

If the well casing fails beneath the seafloor - it's been under a steady high-pressure, high-temperature sandblasting since April 20, and the BOP is reportedly leaning slightly to one side - much of the leaking oil would likely bypass the BOP entirely, possibly raising the flow rate to BP's worst-case scenario estimate of 100,000 barrels per day. In that event, we'd need to immediately deploy a large containment device similar to the "dome" that was initally tried and quickly failed. Something we can lower over the entire BOP and onto the seafloor surrounding the well. Has such a device been designed and built, in case it's needed? If not, why not? It's imprudent to just hope the casing will hang on until a relief well is successful, and it could take weeks to build and test a backup containment device. Let's get to work on that ASAP if we haven't already.

Unless we're willing to risk weeks of uncontrolled flow at 2.5-4.2 million gallons per day.

Bad news today - an ROV bumped into the LMRP containment cap that had recently been diverting about 700,000 gallons of oil a day from the leaking well to vessels at the surface. The LMRP has been removed for repair and, as of right now, oil is gushing unchecked from the Macondo well, possibly at a rate as high as 2.5 million gallons (60,000 barrels) per day. See the spill cam video here.

Monday, June 21, 2010

MODIS Terra and Aqua images on June 18 and June 19 have some cloud-cover problems but still show oil slick and sheen spanning areas of 11,278 square miles and 18,473 square miles respectively, with oil apaprently coming ashore from Gulf Shores, Alabama to points as far east as Seacrest and Rosemary Beach, Florida. Oil is also apparent in Pensacola Bay on the 18th:

Strong thunderstorms form large, dense masses of bright white cloud in this image -- one area of cloud obscures the location of the leaking Macondo well, source of the ongoing BP / Deepwater Horizon oil spill. Oil slicks and sheen viewed through breaks in the cloud cover at least 11,278 square miles (29,210 km2). Oil appears to be making landfall along the beaches of Perdido Key, Alabama, and east along the coast to Destin, Florida. Oil slicks also seem to occur within Pensacola Bay itself. Compare with the MODIS/Aqua image taken the next day, on June 19:

Not as many thunderstorms and cloudy patches on this image, revealing the continuing upwelling of fresh oil around the location of BP's leaking well. Slicks and sheen span 18,473 square miles (47,847 km2) on this image. Thin patches appear to be making landfall from Gulf Shores, Alabama to Perdido Key in Florida, and from Grayton Beach State Park to the Seacrest / Rosemary Beach area along the Florida coast.

Just a quick followup to our last post. The Ocean Saratoga rig is working to plug 26 wells that had been connected to an oil platform damaged (and destroyed, or removed) by Hurricane Ivan in 2004:

The Taylor wells are leaking an average of less than one- third of a barrel of oil each day, the Interior Department said. The leaks have been “substantially reduced” over the years by containment domes and other interventions, Taylor said in a statement yesterday.

1/3 of a barrel is 14 gallons. The slick we measured on June 18 satellite imagery holds an estimated 3,157 gallons of oil, assuming the slick is only 1 micron thick. It would take 225 days, at a rate of 14 gallons per day, to make an oil slick that large. Oil on the surface of the ocean can't survive that long -- especially a slick that's only 1/1000th of a millimeter thick.

The leakage rate from these wells in recent days must be significantly higher, probably in the range of 100-400 gallons per day. If they've been leaking at that rate since Hurricane Ivan, that's a total of 210,000-840,000 gallons of oil. To put it in perspective, less than one day's worth of leakage from BP's Macondo well.

Friday, June 18, 2010

Radar satellite images taken on June 10 and June 18, 2010, show continuing slow leakage from a well at the location of Platform 23051 in the Gulf of Mexico, about 40 miles from the leaking Macondo well that is the source of the ongoing BP / Deepwater Horizon oil spill. Oil from that massive BP spill is visible in the lower right of both images (oil slicks are dark on these images):

Air photos and video shot at the site on June 5 showed a long plume of oil in the water next to a semisubmersible drill rig, the Ocean Saratoga, and no sign of a fixed platform. News accounts and news releases indicate the Ocean Saratoga is working to plug a well that was damaged by a seafloor mudslide during Hurricane Ivan in 2004, and has been leaking at a slow rate ever since. Containment devices are supposed to be capturing much of that oil.

We infer that Platform 23051, installed in the mid-1980s, was destroyed by - or removed shortly after - Hurricane Ivan in 2004; and that the Ocean Saratoga is working at the site formerly occupied by Platform 23051.

The slick apparent on the June 18 image covers 11.95 km2. Assuming an average thickness of 1 micron (1/1000th of a millimeter), that represents a total volume of 3,157 gallons of oil. Certainly this pales in comparison with the BP spill: that well is now estimated to be gushing oil at a rate of 1.47 - 2.52 million gallons (35,000 - 60,000 barrels) per day; the Coast Guard reports that 1.05 million gallons (25,000 barrels) were captured yesterday. But we think it's important to know how common chronic leaks like this are.

Wednesday, June 16, 2010

This MODIS/Aqua satellite image, taken on June 12, has a broad sunglint pattern centered on the eastern Gulf that effectively illuminates the main oil slick as well as areas of what we interpret as much thinner sheen. The bright band of sunglint spanning this image reveals fine structure (squiggly bright lines) in areas to the east of what we interpret as the main area of oil slick; this structure can be caused by natural surfactants, or it may indicate very thin layers of residual sheen related to the ongoing spill. As on June 9, there is some ambiguity in our delineation of the area of slicks and sheen (orange line), which extends across an area of 23,140 square miles (59,932 km2) -- as big as our home state of West Virginia:

Oil appears to be making landfall across 40 miles of coast east of Mobile Bay, from Gulf Shores, Alabama to Perdido Key, Florida. Tendrils of oil, possibly thin sheen, reach toward the Florida coast from Pensacola almost as far east as Panama City. Some news accounts support this analysis.

And the government just revised the estimated leak rate from the well - they now say it's leaking anywhere between 1.5-2.5 million gallons per day, with the containment device currently capturing about 500-600 thousand gallons of that flow. That means that since BP cut the riser and installed the latest containment cap, at least 900 thousand gallons - and possibly as much as 2 million gallons - have entered the Gulf daily. At the high end that's nearly twice as much as the 1.1 million gallon estimate SkyTruth and Dr. Ian MacDonald of Florida State University made back on May 1.

Friday, June 11, 2010

Dr. Ian MacDonald at Florida State University just provided us with this BP memo detailing the spill-rate calculations performed by BP. Click it to see the full-sized version. We guess this is how BP came up with their very low estimated leak rates of 42,000 gallons (1,000 barrels) and 210,000 gallons (5,000 barrels) per day. The official estimated leak rate now stands at 20,000-30,000 barrels per day (and possibly much higher).

Thursday, June 10, 2010

Playing some catch-up from Capital Hill Ocean Week. We served on a panel yesterday and gave a presentation on the spill (starting at 36:10 in this video). Thanks for your patience, we're stretched pretty thin!

Here are MODIS/Terra satellite images of the Gulf from June 7 and June 9. The image taken June 7 shows slick and sheen across an area of 9,075 square miles (23,504 km 2). A large dark area west of the slick may be a low-wind area within the generally bright belt of sunglint west of the Mississippi Delta. There may be slicks or sheen obscured by this low-wind region:

Compare this with the MODIS/Terra taken on June 9, which has a broad sunglint pattern centered on the eastern Gulf that effectively illuminates the main oil slick as well as areas of what we interpret as much thinner sheen. The bright band of sunglint spanning this image reveals fine structure (squiggly bright lines) in areas to the north, south and west of what we interpret as the main area of oil slick; this structure can be caused by natural surfactants, or it may indicate very thin layers of residual sheen related to the ongoing spill. Lots of judgment calls made when encircling the area of slicks and sheen (orange line), but we come up with a total area of 16,434 square miles (42,565 km2):

We don't think the actual area of ocean affected by slicks and sheen nearly doubled in just two days; instead, we think the MODIS image from June 9 was just much more effective at showing those areas than many of the images we've been collecting throughout this incident. And it is possible that some of the area we've delineated contains natural surfactant rather than spilled oil. Again, a difficult image to interpret in some areas.

UPDATE 6/11/10 4pm - We're wondering if Platform 23051 was destroyed by Hurricane Ivan in 2004, and if the Ocean Saratoga rig is actually working at the site of the destroyed platform. This would make a lot of sense. If anyone has information that would confirm (or refute) this, please let us know.

UPDATE 6/11/10 5pm - John Wathen tells me that the pilot collected a GPS location while they flew over the Ocean Saratoga rig last weekend. John gave me the GPS coordinate, and it plots right on top of the MMS-given location coordinate for Platform 23051. So I think the platform was destroyed by Ivan, and the leaking well that the Saratoga is working to plug is the well that was under Platform 23051.

Conclusion: the persistent slicks we've been seeing on multiple satellite images are apparently caused by the continuing leakage from this hurricane-damaged well. It would be great if someone from MMS or the Coast Guard would confirm this.--Some recent media reports about our work related to possible leaks unrelated to the BP spill have gotten a few things wrong. Here's a clarification: based on our analysis of multiple satellite images collected since April 25, we see what appears to be a small but persistent oil slick at or very near the known location of Platform 23051. According to MMS this is a fixed oil platform, installed in the 1980s, that has a crew onboard. If this is indeed a small oil slick, it might indicate a small chronic leak related to that facility; it might also be coming from a natural oil seep on the seafloor at or near the platform. There may be other causes that we are not aware of.

None of this changes our main question: how common are smaller spills like this, whatever their cause? What are the impacts? Is this a problem in the Gulf, or not? Would it be a problem with drilling elsewhere, such as in the Arctic or off the coast of Florida?

Sunday, June 6, 2010

UPDATE 6/8/10 9am - check out video from an aerial overflight of the apparent oil leak next to the Ocean Saratoga semisubmersible drill rig, working ten miles offshore in Mississippi Canyon Block 20. We're still trying to determine if this is the potential leak that we identified on satellite imagery as possibly coming from Platform 23051, or if this is yet another apparent oil leak in the same vicinity.

NOAA actually mentions the oil leak near the Saratoga in this map published back on April 30. The Mobile Register wrote about this yesterday.

UPDATE 6/8/10 3:30pm - This blogger uses some interesting language, but reports that the Ocean Saratoga is working to plug a well that had been damaged by Hurricane Ivan in 2004. No explanation why there would be oil in the water as a result of this plugging operation. This also doesn't explain the possible leak we see on multiple satellite images of Platform 23051.

UPDATE 6/9/10 7:15pm - Some media reports are misrepresenting SkyTruth's work: we never claimed the Ocean Saratoga was leaking oil; our satellite image analysis indicates a possible persistent leak at or near Platform 23051, which is in the same general vicinity in the Gulf. These are two separate structures - one is a mobile drilling unit (MODU), the other is a fixed platform.

--

Three days ago we blogged about a possible small, but persistent, leak from offshore oil platform #23051 in the Gulf of Mexico, not far from the ongoing Deepwater Horizon spill. We asked for confirmation from anyone who might happen to be in the vicinity. Ask, and ye shall receive:

Photograph taken 6/5/10 of apparent oil leak in the vicinity of Platform 23051, courtesy J Henry Fair. Semisubmersible drill rig in foreground; workboat at left where the plume originates at the surface. Note a second plume apparently originating from platform in the background at upper right; this may be Platform 23051 (not yet confirmed).

Professional photographer J Henry Fair flew over the site yesterday using the MMS platform location in our blog post, and took photos of what he found. Here are the two he sent us today. There is an obvious plume of oil in the water next to a semisubmersible drill rig. J Henry identified it as the Ocean Saratoga rig (nice picture here), owned by Diamond Offshore.

The May 17 rig status report available on Diamond Offshore's website (which prominently features a photograph of Senator Mary Landrieu, with the caption "Credit where credit is due") shows the Ocean Saratoga is currently under contract to drill for the same company that owns and operates Platform 23051. The platform may be the one visible in the background of the photo above, apparently trailing another oily-looking plume. So it's possible that we've actually discovered two separate leaks or spills in the same vicinity.

A closer look at the semisubmersible rig, work boat, and apparent plume of oil near the location of Platform 23051 in the Gulf of Mexico, taken June 5, 2010. Photo courtesy J Henry Fair.

J Henry described the workboat at the end of the oil plume as "churning the oil" as if to disperse it more quickly. It's unclear from these pictures if the workboat is itself the source of this oil plume, or if indeed it's motoring around where an oil plume is emerging at the ocean surface in an attempt to break it up. In any event, this spill is certainly large enough to require reporting to the Coast Guard.

According to MMS data, the platform is located at 28.938022 degrees North latitude, 88.970963 degrees West longitude. That's about 12 miles east-southeast of the tip of the South Pass outlet channel of the Mississippi River.

If anyone happens to be in the vicinity of this platform it would be great to get some observations, photos and/or video to document this possible leak or discharge.

Thursday, June 3, 2010

MODIS images today were too cloudy to be useful, but an excellent radar satellite image was taken today of the ongoing Deepwater Horizon oil spill in the Gulf of Mexico. This image, taken from the Envisat satellite using the ASAR radar sensor, shows oil apparently making landfall in Alabama on the east side of Mobile Bay, in the Fort Morgan - Gulf Shores area. An article on the Washington Post website today seems to confirm what we're seeing on the image:

Oil slicks and sheen spread across a total area of about 11,505 square miles (29,796 km2) on this image, which doesn't extend very far west of the Mississippi Delta, and doesn't cover the approach to Florida Straits where we saw possible indications of oil on May 27.

Dr. Ian MacDonald and Dr. Oscar Garcia-Pineda at Florida State University have also been systematically analyzing the radar images of this spill. The animated graphic below shows a detailed look at the northeastern portion of the oil slick as it moves eastward off the Alabama coast and the Florida Panhandle on May 31, June 1 and June 3:

The ongoing Deepwater Horizon oil spill has provided a rare scientific opportunity: for the first time, multiple satellite remote-sensing systems, from visible to infrared to radar, are providing daily images of a large area in the Gulf of Mexico. This systematic imaging is proving useful for measuring the size and location of oil slicks and sheen, and for estimating the rate of leakage from BP's failed Macondo well.

It's also demonstrating another important ability -- here at SkyTruth we think we've discovered a small but possibly chronic leak from an oil platform located a few miles off the Mississippi Delta, unrelated to but not far from BP's leaking well:

Time-series of images showing possible small leak from Platform 23051

We first mentioned this back on May 15. According to GIS data from the Minerals Management Service showing the locations of all fixed oil and gas platforms in the Gulf, the platform that appears to be leaking is identified by Complex ID # 23051. You can look up more info at the MMS website. According to MMS this platform was installed in 1984, and it is manned 24/7 (most platforms in the Gulf are unmanned). The sequence of satellite images above shows what appears to be a small oily slick emanating from the platform location on multiple dates, captured by several different satellite imaging systems. We've observed the slick on Envisat MERIS and ASAR images taken on April 25 and 26, and May 12, 18 and 31; on RADARSAT images taken May 8 and 11; and on COSMO-SkyMed images taken May 11, 14 and 15. (Pet Peeve Alert: These are all foreign satellites, operated by Germany, Italy, Canada. Radar imagery is the go-to tool for detecting and monitoring oil slicks, yet the U.S. does not operate a single civilian radar satellite. Instead, we've been buying radar images of this disaster from other nations. This is nuts.)

On May 27 a scientist from the University of West Florida was flying over the Gulf to investigate the BP oil spill, and noticed an obvious discharge plume coming from a rig - here is one of the pictures she took during that flight:

This appears to be a small jackup drill rig actively drilling in relatively shallow water. The brown plume looks like it could be drilling mud. But along with the apparent oily leak from 23051 this discharge raises a few questions:

How much chronic, day-to-day pollution is associated with offshore drilling?

Who is doing the necessary oversight to minimize this pollution?

How effective is this oversight?

As our vast offshore infrastructure of platforms and pipelines ages, can we effectively identify small chronic problems before they turn into big problems?

All of these questions point to a readily available technical tool that can contribute, right now, to providing some answers: regular monitoring of the Gulf using satellite images from a variety of remote-sensing systems. If the U.S. had such a program we could systematically assess how common smaller pollution events are, and immediately respond in the event of sudden pollution emergencies like the ongoing BP spill, recent pipeline leaks, the offshore and coastal spills that resulted from hurricanes Katrina, Rita and Ike, and other time-critical incidents.

Much of the hardware and trained personnel that could implement a Gulf-wide monitoring system already exists, at the CSTARS facility housed at the University of Miami. CSTARS has their own satellite dishes and image-processing capability. They've been producing gigabytes of satellite imagery since the BP spill began on April 20. But CSTARS only gets activated for this work during emergencies. Maybe it's time to extend that mission and conduct regular, routine, continuous monitoring so we can get a more complete picture of how well our nation's publicly owned waters and offshore resources are being managed.